This project is a first step toward a larger project which would determine the prevalence of primary open angle glaucoma in the Cherokee Indians of Oklahoma. This population is of special interest because it has a high prevalence of type 2 diabetes (perhaps 20% or more). Diabetes may be a significant risk factor in the development and progression of open angle glaucoma. This pilot project would test the feasibility of protocol, response rate and sampling methods. Names will be taken from the computerized registry of the Cherokee Nation and mailed an invitation to be screened for diabetes and glaucoma. Community Health Representatives (tribal employees) will facilitate a positive response. Preliminary testing on all participants will include random blood sugars with glucometer, Goldmann tonometry, slit lamp inspection, optic nerve evaluation, and automated visual fields. Second level testing on glaucoma and diabetes suspects will include fasting blood sugars, repeat tonometry, optic nerve and nerve fiber layer photographs, and Goldmann perimetry. It is hoped to screen 500 persons. This will be the first epidemiological study of glaucoma in this country to test visual fields on all participants, to focus on a minority race, and to include a large number of diabetics.